Apparatus for treating webs

ABSTRACT

An apparatus for impregnating cloth with, for example a dye liquor in which the cloth is moved past a vacuum chamber which removes the air from the cloth and is then immediately subjected to the action of a dyeing bath. The evacuated cloth either is passed through the dye bath or it is moved past the outlet of a dye bath, the dye being fed gravitationally to the cloth in the latter case. An endless rubber belt ensures that there is no loss of vacuum at the vacuum chamber and assists in moving the cloth past the vacuum chamber and dye bath; the cloth is in direct contact with the vacuum chamber which is not rotated.

United States Patent 1191 [111 3,797,281 Norton 1 Mar. 19, 1974 [54] PPR U FOR R TIN WEB 2,817,227 12/1957 Eriksson 68/20 i 2,876,063 3 1959Bond 68/181 R x [75] lnvemor- Dav'd Edward Pepi" Norm", 3,163,03012/1964 WOOdWOl'th 68/20 x Over Alderley, England 2,900,991 8/1959Arnold 68/205 R x S- 3.190.793 6/1965 Starke 68/20 X LlmltedisalfordManchester Primary Examiner-Harvey C. Hornsby Lancashlre England HAssistant Examiner-Phi1ip R. Coe 22' Filed: Mar; 7,1972 Attorney, Agent,or Firm-Richard c. Sughrue An apparatus for impregnating cloth with, forexample [30] Foreign Application Priority Data a dye liquor in which thecloth is moved past a vac- June 12, 1971 Great Britain 27654/71 HumChamber Which removes the air from the clflth and is then immediatelysubjected to the action of a 52 us. c1. 68/19.1, 68/20, 68/22 R, dyeingbath, The evacuated 919th either is Passed 63/205 R through the dye bathor it is moved past the outlet of [51] Int. Cl. Bc 5/02, B050 9/08 a ybath, the y ng fed gr i ion lly o the [58] Field of S ar h 68/19 19 1,20, 22 R, cloth in the latter case. An endless rubber belt ensures63/205 R, 131 R that there is no loss of vacuum at the vacuum chamberand assists in moving the cloth past the vacuum cham- [56] R f e c Ci dher and dye bath; the cloth is in direct contact with UNITED STATESPATENTS the vacuum chamber which is not rotated.

426,875 4/1890 Stiner 68/19 16 Claims, Drawing Figures 1,606,089 11/1926McConnell 2.494,807 1/1950 Haeberlin 1 2,624.189 1/1953 Pendleton 68/19I 26- i 30, 28 3o i 34 l PATENTEBRAR 19 I974 SHEET 1 0F 3 1 APPARATUSFOR TREATING WEBS This invention relates to apparatus for treatingtextile and other webs with liquids and/or fluids. Such liquids and/orfluids may be inter alia, bleaching chemicals dyestuffs, and/orfinishing compounds.

The present invention is particularly concerned with apparatus forimpregnating textile and other webs with such liquids and/or fluids.

Hitherto with conventional methods of impregnation which, for the mostpart,.comprise immersing the web in a tank containing a treating liquidfollowed by squeezing between a pair of rolls, it has been impossible toobtain the desired complete saturation of the webs by the treatingliquid. To assist liquid absorption or pick-up webs have been previouslyprepared by scouring to render it absorbent. When webs are not properlyor uniformly or levelly prepared across the width not only has it beenfound difficult to force liquor into the web but the degree ofabsorption of the liquor by the web frequently varies across the widthwith the result that the appearance of the web is not uniform.

The present invention provides apparatus which increases the absorptionof treating liquid and/or fluid into webs and in consequence whichobviates or mitigates the need for previous securing and preparation inmany cases, and further which ensures at the same time a perfectlyuniform or level saturation and therefore uniform or level effect on theweb across its width.

According to the present invention there is provided apparatus for usein the impregnation treatment of a textile or other web with a liquidand/or a fluid, the apparatus comprising a vacuum chamber having a slotor other opening past which a web can be moved, an impregnation bathimmediately after the vacuum chamber, and an impervious, vacuum-sealingbelt, band or the like for moving the web past the vacuum slot in closecontact therewith and past or through the impregnating bath.

Embodiments of the present invention will now be described, by way ofexample, with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic view of an impregnating apparatus according tothe present invention;

FIG. 2 is a sectional end view of the vacuum chamber and impregnatingbath;

FIG. 3 is a plan view of a wearing member providing vacuum slots oropenings and impregnating medium outlets;

FIG. 4 is a section on the line IV-IV of FIG. 3;

FIG. 5 is a fragmentary underneath plan view corresponding to FIG. 4;

FIG. 6 shows an example of an entry and exit arrangement for theapparatus;

FIG. 7 is a diagrammatic view of an apparatus according to the inventionwhen it is to be used with solvent liquors;

FIG. 8 is a diagrammatic view of another modified apparatus; and,

FIGS. 9 and 10 are a sectional view and a fragmentary underneath planview of a modified wearing plate.

Reference is made firstly to FIG. 1 of the drawings. The apparatuscomprises basically a wetting-out unit consisting of a vacuum box 21 anda liquor box 22 serving as an impregnation unit, and a rubber or otherelas- 2 tomeric endless belt 23 impervious to the treating liquor.

The textile web or cloth which is to be impregnated is indicated at 24.

The web 24 is transported through the wettingout unit between the vacuumbox 21 and liquor box 22 and the rubber belt 23. The web 24 which istrapped between the boxes 21 and 22 and the rubber belt 23 passessuccessively under a vacuum slot and the outlets of the liquor box 22.The web 24 is not subjected to any tension or drag from the suction slotdue to the fact that the belt 23 is driven.

It will be manifest that the rubber belt 23 provides an effective sealto obviate or mitigate loss of vacuum.

The suction circuit is indicated by dotted arrows and comprises thevacuum box 21, a high vacuum receiver 25 and a high vacuum pump 26.

The liquor circuit is indicated by full arrows and comprises the liquorbox 22, a liquor level trough 27 which, in use, is at the same level asthe liquor box 22, a liquor supply tank 28 fed from mixing tanks (notshown) and a drip trough 29.

Pumping traps for the suction and liquor circuits are indicated at 30.

A washing circuit is also provided for the apparatus and is indicated bydot-dash arrows. This circuit uses, say, hot water and serves to washout the receiver 25, the supply tank 28, the liquid level trough 27 andthe liquor box 22 and vacuum box 21.

After impregnation the web 24 :is subjected to means for removing excessliquor. Such extraction means may be either a squeezing nip 31 orsuction extraction. In the latter case, there is a suction box 32 withan appropriate slot which is connected to a suction receiver 33 i and asuction pump 34. The suction box 32 and receiver 33 are connected to thewashing circuit.

In either case excess liquor is returned to the storage tank 28.

Any liquor which is drawn into "the high vacuum line is trapped andpumped into the storage tank 28.

The abovedescribed apparatus is a recirculatory apparatus. Where theapparatus is to be used with liquors unsuitable for recirculation, thestorage tank 28 is omitted and the liquor level trough 27 is feddirectly from mixing tanks (not shown). Also drains are provided atlocations D, the piping between two of these locations and the driptrough 29 and the trough 27 respectively being omitted.

The wetting-out unit will now be described in greater detail.

The unit comprises a tube 35 closed at its bottom by a high densitypolyethylene wearing plate 36 and subdivided internally by a partition37 to define the vacuum box 21 and the impregnation box 22. The tube 35is closed at one end by a plate (not shown) and at its other end abuts aplate formed with an opening (also not shown).

The vacuum circuit is connected to the vacuum box 21 by convenientpiping 48 and the liquor circuit is connected to the impregnation box 22by convenient piping 49.

The wearing plate 36 is most important and is provided with a series ofholes 50 for securing it to the tube 35 by bolts or studs (not shown).The impregnation box outlet is constitutued by an elongate slot 51. Thisconstruction ensures that there is uniform application of the treatingliquor to the web or cloth 24 thus avoiding spotting i.e. non-uniformapplication of the treating liquor. The suction slot or opening isconstituted by two parallel rows of staggered holes 52'with the bottomends of the holes 52 in each row being connected by an elongate slot 53.The provision of these slots 53 ensure uniform removal of the air fromthe cloth or web 24 thus avoiding striping on the cloth or web.

The spacing between the vacuum holes 52 and slots 53 and theimpregnation slot 51 is small, say between one and two inches andpreferably one and a half inches. It is important that this distance beas small as possible to ensure that no air or as little air as possibleenters the evacuated-interstices of the web or cloth 24 before entry ofthe treating liquor.

In a modified wearing plate (FIGS. 9 and 10) the impregnation box outletis constituted by a series of holes 86 communicating with an elongateslot 87, while the vacuum or suction slot is constituted by two parallelrows of staggered holes 88 with the bottom ends of the holes 88 in therow adjacent the vacuum holes 86 being connected by an elongate slot 89.The holes 88 in the other row may also be connected by an elongate slot90.

It is appropriate to mention here that the impervious endless belt 23passes round two rollers or drum 55 and 56, the roller or drum 56 beingdriven as hereinafter described and the roller or drum 55 being mountedso as to apply a tension to the belt 23. This mounting may convenientlybe a pair of arms carrying the roller 55, the arms being pivotal toeffect the tensioning. Alternatively, the roller 55 may be mounted on aslide arrangement.

Various entry and exit arrangements may be used with the apparatus, forexample, entry from wagon or batch and exit to plaiter or batch orpredryer or other machine.

A convenient but non-limitative entry and exit arrangement is shown inFIG. 6.

The entry arrangement comprises entry rails 65, an entry batch 66,scroll and tracking rolls 67, uncurlers 68, driven openers 69, and clothguider 70. These entry arrangement components are not all used togetherbut are optional depending on the kind of material being treated.

The exit arrangement comprises a delivery batch 71, a giant batch 72 ora feed 73 to other machines.

In use a web or cloth 24 is fed through the wettingout unit where it issuccessively evacuated of air and immediately impregnated with treatingliquor as aforesaid, excess moisture being thereafter removed by thesuction slot or squeezing nip.

This apparatus allows total saturation or liquorlogging of the web orcloth with many advantages, viz:

l. Dyeing Levelness and uniformity of shade (in some instances strongershade than normal padding.) Freedom from skitteriness or frostiness.Complete penetration.

Easy impregnation of water-repellent or hydrophobic fibres e.g.synthetic fibres.

Many unscoured fabrics, especially knitted cottons, can be dyed as wellas if they had been scoured. (But it is necessary to confirm that sizeand impurities do not interfere with the dyeing or fixation process).

Elimination of the seam line apparent on circular knit goods pad-dyedconventionally.

2. Bleaching.

By vacuum impregnating the bleach liquor the same degree of whitenesscan be obtained with appreciably less chemical (viz. peroxide) and thereaction time reduced. Vacuum impregnation puts the bleach liquor whereit is needed-right in the fibre almost instantaneously.

3. Finishing.

The more uniform and more thorough penetration of resin into the fibresimproves crease resistance and other such properties.

If the abovedescribed apparatus is used with solvents it is additionallyprovided (see FIG. 7) with hinged covers 74 and a connection 75 to asolvent evaporator. The cloth feed path is indicated at 76 and theporous drum and rubber belt at 77 and 78 respectively.

An alternative construction of apparatus is diagrammatically shown inFIG. 8 and comprises a vacuum chamber or tube 80 connected to a highvacuum pump (not shown) and having in its wall a vacuum slot 81.

An endless belt 83 of an impervious nature is located ajdacne the vacuumslot 81 with one of its runs passing partially around the vacuum chamber80 in the region of the vacuum slot 81. This impervious belt 83 formswith the wall of the vacuum chamber 80 upstream of the vacuum slot 81 inthe direction of travel of a web 84 an impregnation treating bath 85,for example, a dye bath, appropriate side walls (not shown) for the bathbeing provided.

This impervious belt 83. is of relatively substantial proportions and isprovided with propelling means.

In use, all air is evacuated from the web 84 by passing it past thevacuum slot 81 in the wall of the chamber which is, in turn, almostcompletely evacuated by the high vacuum pump. The web 84 is trapped asit passes past the slot 81 between the vacuum chamber 80 and the endlessbelt or band 83 which serves as a seal to prevent loss of vacuum. A

After passing the slot 81 and while still evacuated the web 84 isimmersed in the liquid with which it is desired it should beimpregnated. The web 84 from which all air has been evacuated thoroughlyabsorbs the liquor immediately. It is only necessary thereafter toremove surplus moisture from the web by either passing the web through apair of conventional squeeze rollers or over a second slot to whichsuction is applied to withdraw in this case the surplus moisture whichhas not been absorbed by the fibres of the web. In the event that such asuction device is used for removing the surplus liquor the surface ofthe web opposite to the suction slot is open to the air and there istherefore no question of evacuating the web as when passing over thefirst slot.

The belt 83 need not be endless and the treating bath need not bedefined by the vacuum chamber and the impervious belt.

What is claimed is:

1. Apparatus for use in the impregnation treatment of a web with a fluidcomprising vacuum chamber means, slot means formed in said chamber meansand having a length at least equal to the width of the web to beimpregnated, fluid impervious vacuum-sealing belt means having a widthgreater than the length of said slot means for supporting andtransporting said web, means supporting and driving said web carryingbelt means past said slot means in fluid sealing contact with saidvacuum chamber means, impregnation bath means disposed contiguously tosaid vaccum chamber means and said belt means on the downstream side ofsaid chamber means in the direction of travel of said belt means wherebya web carried by said belt means will be subjected to a fluid in saidbath means immediately subsequent to being subjected to a vacuum bypassage over said slot means.

2. Apparatus as claimed in claim 1 in which said impregnation bath meanshas an impregnating fluid outlet opening directly on to a web which isbeing moved past said outlet in close contiguous contact therewith bysaid vacuum-sealing belt means.

3. Apparatus as claimed in claim 2, in which saidslot means and saidoutlet are disposed closely adjacent to one another.

4. Apparatus as claimed in claim 3, comprising a wearing plateconstituting the bottom of said vacuum chamber means and saidimpregnation bath means and being apertured to provide said slot meansand said outlet.

5. Apparatus as claimed in claim 4, in which said outlet is defined byan elongated slot.

6. Apparatus as claimed in claim 5, in which said slot means and theinterior of said chamber means are interconnected by a row of holesformed in said wearing plate.

7. Apparatus as claimed in claim 4, in which said slot means is definedby two rows of holes in the wearing plate extending transversely to thedirection of travel of said belt means with the holes of one rowstaggered relative to the holes of the other row and with the bottoms ofthe holes in one of the rows merging in an elongated slot at theirtrailing edges in the direction of movement of said belt means, whilethe holes in the other row merge in an elongated slot at their leadingedges in the direction of movement of said belt means.

8. Apparatus as claimed in claim 4, in which said wearing plate isformed of high density polyethylene.

9. Apparatus as claimed in claim 4, in which said wearing plate issubstantially arcuate in the region of the vacuum chamber means andimpregnation bath means, said belt means being endless and passingaround a pair of rollers positioned at opposite ends of said plate toconstrain said belt means to travel in an arcuate path over said wearingplate, means movably mounting one of said rollers for tensioning saidbelt while the other of said rollers is driven.

10. Apparatus as claimed in claim 9, comprising prime mover means fordriving said driven roller.

11. Apparatus as claimed in claim 1 further comprising recirculatorycircuit means including said impregnation bath means, a fluid supplytank connected to the impregnation bath means for feeding a fluid to theimpregnation bath means, a fluid level tank also connected to theimpregnation bath means to ensure topping up of the latter and a driptrough under the impregnation bath means to collect excess fluid, saidimpregnation bath means being disposed for gravitational feed of theimpregnating fluid to a web passing beneath said bath means.

12. Apparatus as claimed in claim 1 further comprising a high vacuumpump and a high vacuum receiver and means connecting said vacuum chambermeans to said high vacuum pump through said high vacuum receiver.

13. Apparatus as claimed in claim 1 further comprising squeezing nipmeans disposed downstream from said bath means in the direction oftravel of said belt means to remove excess fluid from the web.

14. Apparatus as claimed in claim 1 further comprising suction meansdisposed downstream from said bath means in the direction of travel ofsaid belt means which serves to remove excess fluid from the web.

15. Apparatus as claimed in claim 1 further comprising a closed casinghaving hinged covers surrounding and enclosing said vacuum sealing beltmeans, said vacuum chamber means, and said. impregnation bath means andmeans connecting said casing to a solvent extractor.

16. Apparatus as claimed in claim 1 in which said vacuum chamber meansis comprised of a vacuum tube having a vacuum slot therein extendingtransversely of said belt means, said belt means defining with thedownstream wall of the vacuum tube the impregnating bath means wherebysubsequent to passage over said vacuum a web carried by said belt meanswill be passed directly through fluid in said impregnating bath means.

1. Apparatus for use in the impregnation treatment of a web with a fluid comprising vacuum chamber means, slot means formed in said chamber means and having a length at least equal to the width of the web to be impregnated, fluid impervious vacuumsealing belt means having a width greater than the length of said slot means for supporting and transporting said web, means supporting and driving said web carrying belt means past said slot means in fluid sealing contact with said vacuum chamber means, impregnation bath means disposed contiguously to said vaccum chamber means and said belt means on the downstream side of said chamber means in the direction of travel of said belt means whereby a web carried by said belt means will be subjected to a fluid in said bath means immediately subsequent to being subjected to a vacuum by passage over said slot means.
 2. Apparatus as claimed in claim 1 in which said impregnation bath means has an impregnating fluid outlet opening directly on to a web which is being moved past said outlet in close contiguous contact therewith by said vacuum-sealing belt means.
 3. Apparatus as claimed in claim 2, in which said slot means and said outlet are disposed closely adjacent to one another.
 4. Apparatus as claimed in claim 3, comprising a wearing plate constituting the bottom of said vacuum chamber means and said impregnation bath means and being apertured to provide said slot means and said outlet.
 5. Apparatus as claimed in claim 4, in which said outlet is defined by an elongated slot.
 6. Apparatus as claimed in claim 5, in which said slot means and the interior of said chamber means are interconnected by a row of holes formed in said wearing plate.
 7. Apparatus as claimed in claim 4, in which said slot means is defined by two rows of holes in the wearing plate extending transversely to the direction of travel of said belt means with the holes of one row staggered relative to the holes of the other row and with the bottoms of the holes in one of the rows merging in an elongated slot at their trailing edges in the direction of movement of said belt means, while the holes in the other row merge in an elongated slot at theIr leading edges in the direction of movement of said belt means.
 8. Apparatus as claimed in claim 4, in which said wearing plate is formed of high density polyethylene.
 9. Apparatus as claimed in claim 4, in which said wearing plate is substantially arcuate in the region of the vacuum chamber means and impregnation bath means, said belt means being endless and passing around a pair of rollers positioned at opposite ends of said plate to constrain said belt means to travel in an arcuate path over said wearing plate, means movably mounting one of said rollers for tensioning said belt while the other of said rollers is driven.
 10. Apparatus as claimed in claim 9, comprising prime mover means for driving said driven roller.
 11. Apparatus as claimed in claim 1 further comprising recirculatory circuit means including said impregnation bath means, a fluid supply tank connected to the impregnation bath means for feeding a fluid to the impregnation bath means, a fluid level tank also connected to the impregnation bath means to ensure topping up of the latter and a drip trough under the impregnation bath means to collect excess fluid, said impregnation bath means being disposed for gravitational feed of the impregnating fluid to a web passing beneath said bath means.
 12. Apparatus as claimed in claim 1 further comprising a high vacuum pump and a high vacuum receiver and means connecting said vacuum chamber means to said high vacuum pump through said high vacuum receiver.
 13. Apparatus as claimed in claim 1 further comprising squeezing nip means disposed downstream from said bath means in the direction of travel of said belt means to remove excess fluid from the web.
 14. Apparatus as claimed in claim 1 further comprising suction means disposed downstream from said bath means in the direction of travel of said belt means which serves to remove excess fluid from the web.
 15. Apparatus as claimed in claim 1 further comprising a closed casing having hinged covers surrounding and enclosing said vacuum sealing belt means, said vacuum chamber means, and said impregnation bath means and means connecting said casing to a solvent extractor.
 16. Apparatus as claimed in claim 1 in which said vacuum chamber means is comprised of a vacuum tube having a vacuum slot therein extending transversely of said belt means, said belt means defining with the downstream wall of the vacuum tube the impregnating bath means whereby subsequent to passage over said vacuum a web carried by said belt means will be passed directly through fluid in said impregnating bath means. 